The distribution and production of cholesteryl ester transfer protein in the human aortic wall

Cholesteryl ester transfer protein (CETP) has been considered to mediate th e transfer of cholesteryl ester from arterial wall, however, the distributi on and production of CETP in human arterial wall remains unclear. Present s tudy histopathologically demonstrated the distribution of CETP and CETP mRN A in thr human aortic wall by immunohistochemistry and in situ hybridizatio n. While CETP was constantly distributed in the media, the protein was reco gnized within the intima with fibrocellular thickening and atherosclerotic intima. Double immunostaining methods demonstrated CETP expression in smoot h muscle cells in the intima and media. CETP mRNA was detected not only in intimal cells but medial smooth muscle cells. Intimal cells expressing CETP mRNA were considered to be monocyte-derived macrophages and smooth muscle cells by immunohistochemistries using two antibodies against smooth muscle actin and human macrophage on the subserial sections. Our in vivo study pro vides that CETP is produced by smooth muscle cells in the intima and media of human aorta, and it is suggested that arterial smooth muscle cells posit ively participate in the removal of excessive cholesteryl ester from the ar terial wall by CETP production. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.